Conventional refrigeration systems used in the production of frozen desserts and the like typically include a freezing cylinder that receives unfrozen product mix from an inlet section and provides processed product through an outlet section to a filler. In order to process the product mix, the freezing cylinder is initially filled with unfrozen mix. The refrigeration system surrounding the freezing cylinder is started. When the freezing cylinder is filled, a dasher assembly in the freezing cylinder is started so that blades attached to the dasher assembly scrape the freezing cylinder wall to introduce ice crystals formed on the cylinder wall with the product mix.
The viscosity of the product mix increases as its temperature decreases and ice crystals are scraped from the freezing cylinder wall. The increased viscosity is detected by monitoring the load on the dasher motor. When the dasher motor-load rises to a predetermined level, forward flow of the dessert mix begins. In particular, dessert mix and air is supplied under pressure into the freezing cylinder. At the same time, frozen dessert from the freezing cylinder exits to the outlet section and then to processing equipment downstream of the freezing cylinder.
One of the problems associated with known refrigeration systems occurs during a start-up operation of the system or at other instances where the temperature of product lines downstream from the freezing is too high. Otherwise, the viscosity and other characteristics of the processed product is unacceptable for consumption. Accordingly, conventional wisdom dictates that processed frozen dessert must initially be diverted to nonproductive containers when forward flow of product commences until the product lines are sufficiently cooled and product consistency is acceptable to the operator. Thus, a substantial amount of product must be diverted to a rework station due to the improper temperature of the product lines. Inasmuch as various separate processing steps are required for reconditioning the product prior to refreezing, in many instances the product is simply discarded.
In addition, the frozen dessert is either diverted for reconditioning or is destroyed when forward flow of the system is interrupted and then restarted. This may be necessitated, for example, when intervention is required for correcting problems with subsequent packaging stations or with other equipment downstream from the freezing system. In some instances, the product line must be shut down completely and restarted, again resulting in unacceptable loss of product.